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The effect of the angle of suture anchor insertion on fixation failure at the tendon-suture interface after rotator cuff repair: deadman's angle revisited
Strauss, Eric; Frank, Darren; Kubiak, Erik; Kummer, Frederick; Rokito, Andrew
PURPOSE: To evaluate what effect the angle of screw-in suture anchor insertion has on fixation stability at the suture-tendon interface. METHODS: Supraspinatus tendons from 7 matched pairs of human cadaveric shoulders were split, yielding 4 tendons per cadaver. An experimental rotator cuff tear was created and repaired, using a 5.0-mm diameter screw-in suture anchor. In a staggered, matched pair arrangement, the angle of anchor insertion was varied between 45 degrees (deadman's angle) and 90 degrees to the articular surface. Each repair underwent cyclic loading, and 2 failure points were defined: the first at 3 mm of repair site gap formation and the second at the point of complete failure. The number of cycles to failure was compared between the 2 groups. RESULTS: The mean number of cycles to 3-mm gap formation for anchors inserted at 90 degrees was 380. This was significantly higher than for repairs made with the 45 degrees angle of anchor insertion (mean, 297 cycles). Complete failure occurred at a significantly greater number of cycles with the 90 degrees anchors (mean, 443 cycles) compared with the 45 degrees anchors (mean, 334 cycles). CONCLUSIONS: Compared with anchors placed at the current standard of the deadman's angle of 45 degrees, suture anchors placed at 90 degrees to the junction of the greater tuberosity and the humeral head articular surface provided improved soft tissue fixation in an experimental rotator cuff model. CLINICAL RELEVANCE: The angle of suture anchor insertion into the greater tuberosity during rotator cuff repair has an effect on the soft tissue fixation at the tendon-suture interface
PMID: 19501288
ISSN: 1526-3231
CID: 99331
Acute acromioclavicular injuries in adults. L
White, Brian; Epstein, David; Sanders, Samuel; Rokito, Andrew
The acromioclavicular joint is comprised of the articulation between the distal end of the clavicle and the acromion. It functions to anchor the clavicle to the scapula and to the shoulder girdle. The subcutaneous location of this joint makes it vulnerable to injury. It comprises approximately 9% of all injuries to the shoulder girdle. The majority of these injuries occur in males with a male to female ratio of approximately 5:1, and the most common age group affected are those in their 20s. Injuries to the acromioclavicular joint are prevalent in football, rugby, and other contact sports. Given the high incidence of acromioclavicular injuries, it is common for orthopedists, emergency physicians, and physical therapists to recognize and initiate treatment for the full spectrum of this type of injury. The current literature outlines joint biomechanics, various methods of fixation, and outcomes of both nonoperative and operative therapy. This article reviews the anatomy, biomechanics, classification of injury, fixation techniques, and outcomes
PMID: 19226062
ISSN: 1938-2367
CID: 97784
Simultaneous bilateral distal biceps tendon rupture during a preacher curl exercise: a case report [Case Report]
Rokito, Andrew S; lofin, Ilya
Complete rupture of the distal biceps tendon is a rare injury, the overwhelming majority occurring in the dominant arm of males during the fourth to sixth decades of life. Simultaneous bilateral rupture of the distal biceps tendon is an extremely rare occurrence, with only three cases reported in the literature. This unusual injury occurred in a recreational weightlifter during a preacher curl exercise. In this particular case, a 6-week delay in presentation necessitated a staged procedure in which a primary repair was feasible in one elbow, while reconstruction using allograft tissue was required in the contralateral elbow. Satisfactory results for both elbows were achieved, with return to weightlifting by one year following surgery
PMID: 18333833
ISSN: 1936-9719
CID: 79558
MRI quantitative morphologic analysis of patellofemoral region: lack of correlation with chondromalacia patellae at surgery
Endo, Yoshimi; Schweitzer, Mark E; Bordalo-Rodrigues, Marcelo; Rokito, Andrew S; Babb, James S
OBJECTIVE: In numerous studies, the morphologic features of the patellofemoral joint have been analyzed on radiographs. The objective of this study was to assess patellofemoral measurements on MR images and to correlate the measurements with the presence or absence of chondromalacia patellae confirmed at surgery. MATERIALS AND METHODS: Axial and sagittal MR images of 98 knees (97 patients) were evaluated. Lateral and medial patellar facet lengths, lateral-to-medial facet length ratio, and interfacet angle were measured at three levels through the patella. Trochlear depth was measured on an axial slice. Patella and patellar tendon lengths, patellar tendon-to-patella ratio, and overlap of the patellar and trochlear articular cartilages were measured on sagittal slices. These measurements in knees with chondromalacia patellae were compared with those in knees without chondromalacia patellae. For assessment of reproducibility, axial measurements were repeated by a second observer. RESULTS: There was no statistically significant difference in any of the axial and sagittal slice measurements between knees with and those without chondromalacia patellae. Interobserver reliability was excellent for measurements of trochlear depth and measurements in the superior and middle aspects of the patella. Measurements through the inferior patella were slightly less reproducible. CONCLUSION: The results of our study with MRI confirmed many previous radiographic findings. Although we did not find correlation between the presence of chondromalacia patellae and the patellofemoral indexes we analyzed, it is possible that the results of further investigations incorporating different grades of chondromalacia and different locations along the patellar articular surface may lead to further insight regarding the morphologic risk factors for chondromalacia patellae
PMID: 17954655
ISSN: 1546-3141
CID: 75394
Arthroscopic revision of Bankart repair
Neri, Brian R; Tuckman, David V; Bravman, Jonathan T; Yim, Duke; Sahajpal, Deenesh T; Rokito, Andrew S
The success of revision surgery for failed Bankart repair is not well known. This purpose of this study was to report the success rates achieved using arthroscopic techniques to revise failed Bankart repairs. Twelve arthroscopic revision Bankart repairs were performed on patients with recurrent unidirectional shoulder instability after open or arthroscopic Bankart repair. Follow-up was available on 11 of the 12 patients at a mean of 34.4 months (range, 25-56 months). The surgical findings, possible modes of failure, shoulder scores (Rowe score, University of California Los Angeles [UCLA], Simple Shoulder Test), and clinical outcome were evaluated. Various modes of failure were recognized during revision arthroscopic Bankart repairs. Good-to-excellent results were obtained in 8 patients (73%) undergoing revision stabilization according to Rowe and UCLA scoring. A subluxation or dislocation event occurred in 3 (27%) of the 11 patients at a mean of 8.7 months (range, 6-12 months) postoperatively. Arthroscopic revision Bankart repairs are technically challenging procedures but can be used to achieve stable, pain-free, functional shoulders with return to prior sport. Owing to limited follow-up and the small number of patients in this study, we were unable to conclude any pattern of failure or selection criteria for this procedure
PMID: 17531511
ISSN: 1532-6500
CID: 74157
ACL injuries in the skeletally immature patient
Schachter, Aaron K; Rokito, Andrew S
Anterior cruciate ligament injuries in the pediatric and adolescent population are becoming more common with the trends of increased participation in competitive athletics in younger children. The natural history of this injury is similar to that of the adult and results in frequent reinjury, instability, and debilitation. Delayed reconstruction has proven to be a clinically effective treatment method but requires a prolonged restriction of competitive athletics. Reconstruction in the acute and subacute period has been shown by many authors to be a successful, reproducible treatment regimen. Nonetheless, the unique pitfalls of ACL reconstruction in a skeletally immature patient must not be overlooked. A thorough preoperative evaluation for leg-length discrepancy or subtle angular deformity is essential to identify the presence of an entity that might otherwise be attributed to surgical complication. For the patient nearing skeletal maturity with little growth remaining, we recommend the standard tunnel positioning and the use of soft-tissue graft. For younger patients who have significant growth remaining, alternative physeal 'safe' procedures should be considered. No prospective, randomized studies compare the clinical success of graft type, graft placement, or graft fixation in this age group. Further follow-up of existing study groups and prospective research is warranted to fine-tune the result-based decision making for treatment of this injury
PMID: 17539208
ISSN: 0147-7447
CID: 73113
Glove tears during arthroscopic shoulder surgery using solid-core suture
Kaplan, Kevin M; Gruson, Konrad I; Gorczynksi, Chris T; Strauss, Eric J; Kummer, Fred J; Rokito, Andrew S
PURPOSE: Surgeons have noticed an increased incidence of finger lacerations associated with arthroscopic knot tying with solid-core suture material. This study examines glove perforations and finger lacerations during arthroscopic shoulder surgery. METHODS: We collected 400 surgical gloves from 50 consecutive arthroscopic shoulder repair procedures using No. 2 solid-core sutures. Two surgeons using double gloves were involved in every case, with one being responsible for tying all knots. Powder-free latex gloves were worn in all cases. Knots consisted of a sliding stitch of the surgeon's preference followed by 3 half-hitches via a knot-pusher instrument. All gloves were inspected grossly and then tested for tears with an electroconductivity meter. RESULTS: The knot-tying surgeon had significantly more glove tears than the control (P < .01). Tears were localized to the radial side of the index finger of the glove at the distal interphalangeal joint in all cases. Of the tying surgeon's gloves, 68 (34%) were found to have tears. These included 17 inner gloves (17%) and 51 outer gloves (51%). If an inner glove was torn, the corresponding outer glove was torn in all cases. A mean of 3.96 knots were tied in each case. There was a significantly higher incidence of inner glove tears when more than 3 knots were tied (P < .03). There was no significant difference in glove tears between suture types. Finger lacerations did occur in the absence of glove tears. However, in the presence of an inner glove tear, there was a statistically significant association with a finger laceration at the corresponding level (P < .03). CONCLUSIONS: Intraoperative glove tears and subsequent finger lacerations occur with a high frequency when arthroscopic knots are tied with solid-core suture material. Risk can potentially be minimized by frequent glove changes or use of more durable, less penetrable gloves. CLINICAL RELEVANCE: This study addresses surgeon and patient safety during arthroscopic shoulder surgery
PMID: 17210427
ISSN: 1526-3231
CID: 70320
Posterolateral corner injuries of the knee
Frank, Joshua B; Youm, Thomas; Meislin, Robert J; Rokito, Andrew S
The posterolateral region of the knee is an anatomically complex area that plays an important role in the stabilization of the knee relative to specific force vectors at low angles of knee flexion. A renewed interest in this region and advanced biomechanical studies have brought additional understanding of both the anatomy and the function of posterolateral structures in knee stabilization and kinematics. Through sectioning and loading studies, the posterolateral corner has been shown to play a role in the prevention of varus angulation, external rotation, and posterior translation. The potential for long-term disability from these injuries may be related to increased articular pressure and chondral degeneration. The failure of the reconstruction of cruciate ligaments may be due to unrecognized or untreated posterolateral corner injuries. Various methods of repair and reconstruction have been described and new research is yielding superior results from reconstruction of this region
PMID: 17581102
ISSN: 1936-9719
CID: 73804
Magnetic resonance imaging evaluation of the ulnar collateral ligament in young baseball pitchers less than 18 years of age
Jazrawi, Laith M; Leibman, Matt; Mechlin, Mike; Yufit, Pavel; Ishak, Charbel; Schweitzer, Mark; Rokito, Andrew
INTRODUCTION: It has been shown that the asymptomatic, dominant elbow of professional baseball pitchers can demonstrate magnetic resonance (MR) imaging signal abnormalities of the ulnar collateral ligament (UCL) consistent with a strain. The purpose of this study was to determine if younger, asymptomatic, adolescent baseball pitchers exhibit similar signal abnormalities in the UCL. METHODS: Magnetic resonance images of both elbows of 14 asymptomatic, young male baseball pitchers (ranging in age from 12 to 20 years) were performed on an outpatient basis using a 1.5-T Sigma MRI unit with a dedicated extremity coil to obtain T1 and T2 coronal and axial images which were subsequently evaluated by a musculoskeletal radiologist. Chronic tears of the UCL were suspected if the signal was attenuated or absent. Magnetic resonance images of the UCL were also evaluated for high-intensity signal or thinning. Morphologic changes such as complete tears, avulsions or thickening were identified. The images were classified into 4 grades from 0 to 3 depending on the degree of signal abnormality. RESULTS: No discrete tears were found in any of the subjects. For the dominant pitching arm, 4 of 14 subjects had increased thickness of the ulnar collateral ligament, 3 of 14 demonstrated Grade 1 changes, and 11 of 14 demonstrated no abnormal signal within the ligament. No focal tears were present in any of the subjects. Contralateral elbows in 13 of 14 patients demonstrated Grade 0 signals with 1 patient demonstrating morphological thickening of the ligament without increased signal. DISCUSSION: Signal abnormalities in the throwing elbow of asymptomatic, adolescent pitchers were uncommon. These pitchers may not have experienced sufficient pitching time to develop changes in the UCL
PMID: 16878828
ISSN: 0018-5647
CID: 69065
A biodegradable button to augment suture attachment in rotator cuff repair
Bravman, Jonathan T; Guttman, Dan; Rokito, Andrew S; Kummer, Frederick J; Jazrawi, Laith M
Recent experimental studies suggest that the use of suture anchors for rotator cuff tear (RCT) repair transfers the 'weak link' to the suture-tendon interface where failure occurs as the sutures cut through the tendon. The purpose of this study was to evaluate the effect of using a suture augmentation button on the fixation strength of rotator cuff tendon repair. A 1.5 cm by 2 cm defect was created in the supraspinatus tendon of seven cadaveric shoulder pairs and two suture anchors inserted in each humerus for suture attachment. For one of each pair, the defect was repaired with sutures placed in a horizontal mattress configuration. The other side was repaired with the sutures being passed through low profile, bioabsorbable buttons placed on the bursal tendon surface prior to knot tying. The supraspinatus tendon was cyclically loaded at a physiologic rate and load (33 mm/sec and 180 N, respectively). The number of loading cycles was recorded when the specimens developed 0.75 cm and 1.5 cm gaps at the repair site. The specimens were then tested to failure. Specimens in the unaugmented group developed 0.75 cm and 1.5 cm gaps at an average of 135 cycles and 362 cycles, respectively. The button augmented group developed these gaps at average of 420 cycles and 708 cycles, respectively. These differences were statistically significant (p < 0.05). The gaps progressively increased in all specimens, which eventually failed by suture cutting through tendon in all specimens. This study demonstrates that in vitro, suture augmentation with a low profile, bioabsorbable button provides significantly enhanced fixation when using suture anchors to repair torn rotator cuff tendon. This device may be a useful adjunct to current methods of rotator cuff repair
PMID: 16878833
ISSN: 0018-5647
CID: 69067